Many window frames are provided with grooves into which accessories can be snap fitted. This is particularly true of up to date vinyl window frames where other vinyl components having the ability to flex can be snap locked into the accessory groove.
In many of the known vinyl window frames, the accessory groove can either be permanently exposed or they may be covered by a strip which needs to be removed at the time of installation of the window. In the later case, the reason the groove remains covered is to protect against the build up of dirt and the like in the groove or to keep the groove covered if no accessories are to be fitted to the frame.
The problem encountered with existing vinyl window frames having covered accessory grooves is that the covering material is not easily removable from the frame. The installer requires a sharp knife and a good eye to determine where the covering material should be cut off of the frame.